US20050075122A1 - Wireless transceivers, methods, and computer program products for restricting transmission power based on signal-to-interference ratios - Google Patents
Wireless transceivers, methods, and computer program products for restricting transmission power based on signal-to-interference ratios Download PDFInfo
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- US20050075122A1 US20050075122A1 US10/612,373 US61237303A US2005075122A1 US 20050075122 A1 US20050075122 A1 US 20050075122A1 US 61237303 A US61237303 A US 61237303A US 2005075122 A1 US2005075122 A1 US 2005075122A1
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- sirs
- sync
- wireless transceiver
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- transmission power
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/30—TPC using constraints in the total amount of available transmission power
- H04W52/36—TPC using constraints in the total amount of available transmission power with a discrete range or set of values, e.g. step size, ramping or offsets
- H04W52/367—Power values between minimum and maximum limits, e.g. dynamic range
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/18—TPC being performed according to specific parameters
- H04W52/22—TPC being performed according to specific parameters taking into account previous information or commands
- H04W52/228—TPC being performed according to specific parameters taking into account previous information or commands using past power values or information
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/18—TPC being performed according to specific parameters
- H04W52/28—TPC being performed according to specific parameters using user profile, e.g. mobile speed, priority or network state, e.g. standby, idle or non transmission
- H04W52/283—Power depending on the position of the mobile
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04W—WIRELESS COMMUNICATION NETWORKS
- H04W52/00—Power management, e.g. TPC [Transmission Power Control], power saving or power classes
- H04W52/04—TPC
- H04W52/18—TPC being performed according to specific parameters
- H04W52/28—TPC being performed according to specific parameters using user profile, e.g. mobile speed, priority or network state, e.g. standby, idle or non transmission
- H04W52/288—TPC being performed according to specific parameters using user profile, e.g. mobile speed, priority or network state, e.g. standby, idle or non transmission taking into account the usage mode, e.g. hands-free, data transmission, telephone
Definitions
- the invention disclosed and claimed herein generally relates to wireless transceivers and methods for estimating the signal-to-interference ratios (SIRs) of received signals, and more particularly to restricting changes that are allowed to the transmission power based on the SIR.
- SIRs signal-to-interference ratios
- Power control is important for capacity and efficiency in code division multiple access (CDMA) communication systems. For example, if a mobile terminal is located close to a base station, the power level of signals transmitted from the mobile terminal to the base station, in the absence of power adjustment, would be comparatively high. This could interfere with transmissions from other mobile terminals located farther from the base station. Conversely, the power level of signals transmitted from a mobile terminal which is located far from the base station, in the absence of power adjustment, could be comparatively weak. Accordingly, some communication systems, including, for example, wideband CDMA (WCDMA) systems, provide a transmission power control (TPC) command by which a base station can adjust the transmission power of a mobile terminal.
- WCDMA wideband CDMA
- TPC transmission power control
- Power control can involve the base station estimating the signal-to-interference ratios (SIRs) of received signals, such as, for example, received pilot symbols in a CDMA system. If the SIRs of a received signal are lower than a threshold value, a command or adjustment signal is sent to the transmitting mobile terminal to increase its transmission power. The command is sent on the reverse link, i.e. the down link. When the estimated SIRs are higher than the threshold value, a command to decrease transmission power is sent by the base station to the transmitting mobile terminal. Base station transmission power may also similarly be controlled by the mobile terminal.
- SIRs signal-to-interference ratios
- a mobile terminal should stop transmitting when the quality of the signal received from a transmitting base station falls below a threshold synchronization value, which may indicate that the mobile terminal has become out-of-sync with the transmitting base station. Accordingly, detection of when the mobile terminal is in-sync or out-of-sync with a transmitting base station can be important to avoid unnecessarily dropping calls, or conversely, to avoid continuing to transmit and possibly degrade the capacity of the base station after the mobile station can no longer effectively communicate with the base station.
- 3GPP 3rd Generation Partnership Project
- a mobile terminal is considered to have become out-of-sync, and therefore should stop transmitting, when the Dedicated Physical Channel Signal to Interference Ratios (DPCH-SIR), averaged over 160 milliseconds, is below a threshold value.
- DPCH-SIR Dedicated Physical Channel Signal to Interference Ratios
- the 3GPP standard also provides that a mobile terminal is considered to be in-sync, and may transmit, when the DPCH-SIR, averaged over 160 milliseconds, is above a threshold value.
- Various embodiments of the present invention provide a method for controlling transmission power from a wireless transceiver.
- Signal to interference ratios SIRs
- An out-of-sync condition between the wireless transceiver and the other wireless device is identified based on the SIRs.
- the other wireless device may, for example, be a base station or a mobile terminal. Changes to the transmission power from the wireless transceiver are restricted based on the SIRs and when an out-of-sync condition has not been identified.
- Restricting increase of the transmission power may avoid or prevent the wireless transceiver from unnecessarily increasing or spiking its transmission power, and possibly interfering with communications between other communication devices, after it may have lost its ability to effectively communicate with the other wireless device.
- restricting a decrease of the transmission power may avoid an unnecessarily dropped connection.
- FIG. 1 illustrates a block diagram of a wireless communication system according to some embodiments of the present invention.
- FIG. 2 illustrates a block diagram of a transceiver according to some embodiments of the present invention.
- each block of the block diagrams and/or operational illustrations, and combinations of blocks in the block diagrams and/or operational illustrations can be implemented by radio frequency, analog and/or digital hardware, and/or computer program instructions.
- These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, and/or other programmable data processing apparatus in a mobile terminal, such that the instructions, which execute via the processor of the computer and/or other programmable data processing apparatus, create means for implementing the functions/acts specified in the block diagrams and/or operational block or blocks.
- These computer program instructions may also be stored in a computer-readable memory that can direct a mobile terminal to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions which implement the functions/acts specified in the block diagrams and/or operational block or blocks. It should also be noted that in some alternate implementations, the functions/acts noted in the blocks may occur out of the order noted in the operational illustrations. For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
- FIG. 1 illustrates an exemplary wireless communication system that includes a mobile terminal 10 that communicates with a wireless communications network 30 over a radio frequency communication channel 28 .
- the wireless communication system is assumed to be a WCDMA system that is compliant with the 3GPP specification.
- the mobile terminal 10 controls its transmission power over the communication channel 28 in response to a transmission power control (TPC) command from the network 30 .
- the mobile terminal 10 also controls its transmission power based on the quality of signals received from the network 30 .
- the mobile terminal 10 may stop transmitting when received signal quality falls below a threshold level, which may indicate that the mobile terminal is out-of-sync or that it otherwise may not be able to effectively communicate with the network 30 .
- the mobile terminal 10 may determine signal quality by estimating signal to interference ratios (SIRs) from pilot signals received from the network 30 .
- SIRs signal to interference ratios
- the mobile terminal 10 stops transmitting, and may thereby avoid interfering with communications between the network 30 and other mobile terminals. Conversely when the estimated SIRs exceed the threshold value, the mobile terminal 10 may begin and/or resume transmission.
- the mobile terminal 10 may remove bias from the SIR estimates according to the various embodiments of the present invention, which may allow more accurate detection of the out-of-sync and/or in-sync condition.
- the mobile terminal 10 may also restrict or prevent an increase and/or decrease of its transmission power based on the SIRs and when an out-of-sync condition has not been identified. For example, when the received signal quality (represented by the estimated SIRs) is below a threshold amount, but the mobile terminal 10 determines that it is in-sync such that it can continue transmitting, the mobile terminal 10 may ignore, or may modify its reaction to, a received TPC command that commands an increase or decrease in transmission output power.
- restricting or preventing an increase in transmission output power may avoid or prevent the mobile terminal 10 from unnecessarily interfering with communications between the network 30 and other mobile terminals when the mobile terminal 10 is uncertain about whether the channel conditions are sufficient to continue communication with the network 30 .
- restricting decrease in the transmission output power may avoid unnecessarily dropping calls.
- the mobile terminal 10 may include a portable housing 12 , a keyboard/keypad 14 , a display 16 , a speaker 18 , a microphone 20 , a processor 22 , a memory 24 , and a transceiver 26 .
- the memory 24 may include one or more erasable programmable read-only memories (EPROM or Flash EPROM), battery backed random access memory (RAM), magnetic, optical, or other digital storage device, and may be separate from, or at least partially within, the processor 22 .
- the mobile terminal 10 may, thereby, communicate with the network 30 using radio frequency signals.
- the radio frequency signals may be communicated through an antenna 26 over the communication channel 28 with the network 30 .
- a “mobile terminal” includes, but is not limited to, a cellular mobile terminal; a personal communication terminal that may combine a cellular mobile terminal with data processing, facsimile and data communications capabilities; a personal data assistance (PDA) that can include a wireless transceiver, pager, Internet/intranet access, local area network interface, wide area network interface, Web browser, organizer, and/or calendar; and a computer or other device that includes a wireless transceiver.
- PDA personal data assistance
- the mobile terminal 10 may be configured to communicate according to one or more wireless communication protocols, including, but not limited to, ANSI-136, GSM, code division multiple access (CDMA), wideband-CDMA, CDMA2000, Enhanced Data Rates for GSM Evolution (EDGE), Universal Mobile Telecommunications System (UMTS), a wireless local area network (WLAN) protocol, including IEEE 802.11b-g, and Bluetooth, satellite protocols, private land mobile radio protocols, including PROJECT-25 and Tetra, and/or other communication protocols.
- Communication protocols as used herein may specify the information communicated, the timing, the frequency, the modulation, and/or the operations for setting-up and/or maintaining a communication connection.
- FIG. 2 illustrates a transceiver 200 that may, for example, be used in the mobile terminal 10 shown in FIG. 1 according to various embodiments of the present invention.
- Information that is to be transmitted may be modulated by a modulator 202 and transmitted by a transmitter 204 through an antenna 206 .
- the transmitter 204 controls its output transmission power based on a power level signal 208 from a combiner 221 , and stops transmitting (reduces its transmission power to a very low value or substantially zero) based on a transmission enable signal 210 from an out-of-sync detector 226 .
- Signals from the antenna 206 are received by a receiver 212 where they are downconverted and sampled, and then coupled to a transmit power control (TPC) decoder 214 , a SIR estimator 216 , a RAKE receiver 218 , and a delay estimator 220 .
- the RAKE receiver 218 has L delay taps or RAKE fingers.
- the delay estimator 220 estimates RAKE delays from the sampled received signal.
- CPICH common pilot channel
- the channel estimates are coupled to the Rake receiver 218 for combining with the received sampled signal, and are coupled to the TPC decoder 214 .
- the TPC decoder decodes the received sampled signal to identify a TPC command from the network 30 , and uses the TPC command to generate a control signal, which is coupled through the combiner 221 to the transmitter 204 , to control the output transmission power of the transmitter 204 . Accordingly, the network 30 may transmit a TPC command to the transceiver 200 to control its output transmission power.
- the SIR estimator 216 also generates an estimate of interference in the received signal.
- the interference may be estimated using the CPICH, and may then be transformed to an estimate of the interference in the dedicated physical channel (DPCH) using a spreading factor difference between the CPICH and the DPCH.
- An estimate of the dedicated signal power may be made using, for example, dedicated pilot channel symbols.
- Signal to interference ratios SIRs may then be estimated using the estimated interference for the DPCH and the estimated dedicated signal power.
- the SIR estimates are coupled to a TX limit filter 222 and a sync filter 224 .
- the TX limit filter 222 and the sync filter 224 can remove at least a portion of bias in the SIR estimates based upon the number of dedicated pilot channel symbols (NDPCH) that are used for channel estimation and/or the number of RAKE fingers used to estimate the SIRs, as will be discussed later herein with regard to further embodiments of the filters.
- NDPCH may be known based on the slot format of the data channel 28 which is provided by the network 30 during the setup of the connection.
- the sync filter 224 generates a filtered SIR signal by, for example, averaging and/or integrating the SIR estimates over a predetermined time.
- the filtered SIR signal is compared by the out-of-sync detector 226 to an out-of-sync threshold.
- the out-of-sync detector 226 determines that an out-of-sync condition has occurred and substantially reduces the output transmission power of the transmitter 204 to, for example, about zero. Accordingly, the transmitter 204 may be substantially turned-off when an out-of-sync condition is detected.
- the transmit (TX) limit filter 222 may operate similar to the sync filter 224 , except that it may have a faster response to rapid changes in the SIRs. Accordingly, an abrupt decrease in the received SIR may be indicated earlier by the filtered SIR signal from the TX limit filter 222 than by the filtered SIR signal from the sync filter 224 .
- a TX limit detector 228 compares the filtered SIR signal from the TX limit filter 222 to a TX limit threshold. When the filtered SIR signal is below, or satisfies, the TX limit threshold, the TX limit detector 228 restricts or prevents changes in the transmission output power of the transmitter 204 .
- the TX limit detector 228 may restrict the transmission power of the transmitter 204 to limited changes and/or may essentially latch (e.g., freeze) the transmission power to a power level, such as a current or previous power level.
- the transmission power level may be latched by, for example, using a limit signal 230 to latch the output power level signal 208 from the combiner 221 to the power level associated with a current TPC command or an earlier TPC command, such as a TPC associated with an earlier slot.
- the transmission power may be restricted to limited changes and/or latched to a power level to preclude such incorrect increase or decrease.
- the output transmission power level may continue to be restricted to limited changes and/or latched until the signal quality sufficiently improves as determined by the TX limit detector 228 , or until the signal quality sufficiently degrades so that the transmitter is essentially turned-off by the out-of-sync detector 226 .
- the threshold values used by the TX limit detector 228 and/or the out-of-sync detector 226 may be based on a desired sensitivity of the transceiver 200 to signal quality conditions where transmission power changes should be restricted or where transmission power should be reduced to about zero.
- Bias or error between the estimated SIRs and the actual SIRs may be at least partially removed by a bias removal module that may be part of the TX limit filter 222 and/or the sync filter 224 .
- Removing bias from the filtered SIR estimates may improve the ability of the TX limit detector 228 and/or the out-of-sync detector 226 to more accurately and/or quickly detect signal quality conditions in which the transmission power should be restricted or turned-off, which may be particularly advantageous for low SIR values.
- the TX limit filter 222 and the sync filter 224 may remove at least a portion of bias in the SIR estimates based upon the number of dedicated pilot channel symbols (NDPCH) that are used for channel estimation and/or the number of RAKE fingers that are used to estimate the SIRs.
- NDPCH dedicated pilot channel symbols
- Bias may be estimated and at least partially removed from the estimated SIRs as described below.
- the threshold values that should be used by the TX limit detector 228 and the out-of-sync detector 226 may be determined as described below.
- In-sync and out-of-sync threshold values, Q in and Q out , respectively, and the TX limit threshold value (Q TX — LIMIT ) may be determined based on a relationship between SIR-symbol energy and combined TPC energy. This relationship may depend upon, for example, the number of TPC symbols N TPC , and/or the number of RAKE fingers used to estimate the SIRs.
- these equations for thresholds, Q in , Q out , and Q TX — LIMIT may be written to include the above-described bias compensation, and may be based on state information including, for example, whether a mobile terminal is in a soft handover mode or a compressed mode.
- the spreading factor may be reduced by a factor of 2 and the DPCH E c power (where E c is the chip energy) may be doubled.
- Compressed mode may be handled by using slot formats ending with A and B.
- Compressed mode slots may use slot formats ending with a “B”, for which the number of DPCH pilot symbols and number of TPC symbols have been doubled to compensate for the spreading factor reduction. Accordingly, the pilot energy and TPC bit energy per time unit may be kept about constant.
- the value N DPCH entering into the filters see Equation (8), may be changed based on the slot format, such as has been described for the non-compressed mode case.
- the thresholds Q in , Q out , and Q TX — LIMIT may be determined with N TPC set to N TPC for slot format A.
- the filtered SIR values from the TX limit filter 222 may be noisier than those of the sync filter 224 .
- the TX limit threshold value used by the TX limit detector 228 may be lower than the out-of-sync threshold value used by the out-of-sync detector 226 so as to reduce the occurrence of unwanted restriction of the output transmission power level due to noise fluctuations in the SIRs.
- the TX limit threshold value may be ⁇ 7 dB and the out-of-sync threshold value may be ⁇ 5 dB.
- the transmission power level may be restricted to an earlier output power level of an earlier slot.
- the filtered SIR value from the sync filter 224 is less than an out-of-sync threshold, the transmitter 204 may be effectively turned-off by reducing the transmission power level to essentially zero.
- a transceiver may be provided as shown in FIG. 2 except that the TX limit filter 222 may be eliminated and the filtered SIR signal from the sync filter 224 may be coupled to both the TX limit detector 228 and the out-of-sync detector 226 .
- the threshold value of the TX limit detector 228 may be based on the threshold value of the out-of-sync detector 226 .
- the threshold that may be used to cause restriction of transmission power changes may be set a predetermined amount above the threshold used to identify an out-of-sync condition. Accordingly, a degraded received signal may satisfy the threshold for restricting power changes before it satisfies the threshold for turning off the transmitter 204 .
- a base station or another wireless device may restrict changes to its transmission power based on the operations and/or wireless transceiver described herein.
Abstract
Description
- This application claims the benefit of provisional Application No. 60/447,238, filed Feb. 13, 2003, entitled Fast Out-Of-Synch Detector For WCDMA, the disclosure of which is hereby incorporated herein by reference in its entirety as if set forth fully herein.
- The invention disclosed and claimed herein generally relates to wireless transceivers and methods for estimating the signal-to-interference ratios (SIRs) of received signals, and more particularly to restricting changes that are allowed to the transmission power based on the SIR.
- Power control is important for capacity and efficiency in code division multiple access (CDMA) communication systems. For example, if a mobile terminal is located close to a base station, the power level of signals transmitted from the mobile terminal to the base station, in the absence of power adjustment, would be comparatively high. This could interfere with transmissions from other mobile terminals located farther from the base station. Conversely, the power level of signals transmitted from a mobile terminal which is located far from the base station, in the absence of power adjustment, could be comparatively weak. Accordingly, some communication systems, including, for example, wideband CDMA (WCDMA) systems, provide a transmission power control (TPC) command by which a base station can adjust the transmission power of a mobile terminal.
- Power control can involve the base station estimating the signal-to-interference ratios (SIRs) of received signals, such as, for example, received pilot symbols in a CDMA system. If the SIRs of a received signal are lower than a threshold value, a command or adjustment signal is sent to the transmitting mobile terminal to increase its transmission power. The command is sent on the reverse link, i.e. the down link. When the estimated SIRs are higher than the threshold value, a command to decrease transmission power is sent by the base station to the transmitting mobile terminal. Base station transmission power may also similarly be controlled by the mobile terminal.
- In some communication systems, such as 3rd Generation Partnership Project (3GPP) standard communications systems, a mobile terminal should stop transmitting when the quality of the signal received from a transmitting base station falls below a threshold synchronization value, which may indicate that the mobile terminal has become out-of-sync with the transmitting base station. Accordingly, detection of when the mobile terminal is in-sync or out-of-sync with a transmitting base station can be important to avoid unnecessarily dropping calls, or conversely, to avoid continuing to transmit and possibly degrade the capacity of the base station after the mobile station can no longer effectively communicate with the base station.
- According to the 3GPP standard, a mobile terminal is considered to have become out-of-sync, and therefore should stop transmitting, when the Dedicated Physical Channel Signal to Interference Ratios (DPCH-SIR), averaged over 160 milliseconds, is below a threshold value. The 3GPP standard also provides that a mobile terminal is considered to be in-sync, and may transmit, when the DPCH-SIR, averaged over 160 milliseconds, is above a threshold value. A further explanation of this requirement is provided by the 3rd Generation Partnership Project; Physical Layer Procedures (FDD), 3GPP TS 25.101, chapter 6.4.4, (2002-06), 2002, and by the 3rd Generation Partnership Project; Physical Layer Procedures (FDD), 3GPP TS 25.214, chapter 4.3.1.2, (2002-06), 2002.
- Various embodiments of the present invention provide a method for controlling transmission power from a wireless transceiver. Signal to interference ratios (SIRs) are estimated for a signal that is received from another wireless device. An out-of-sync condition between the wireless transceiver and the other wireless device is identified based on the SIRs. The other wireless device may, for example, be a base station or a mobile terminal. Changes to the transmission power from the wireless transceiver are restricted based on the SIRs and when an out-of-sync condition has not been identified. Restricting increase of the transmission power may avoid or prevent the wireless transceiver from unnecessarily increasing or spiking its transmission power, and possibly interfering with communications between other communication devices, after it may have lost its ability to effectively communicate with the other wireless device. On the other hand, restricting a decrease of the transmission power may avoid an unnecessarily dropped connection.
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FIG. 1 illustrates a block diagram of a wireless communication system according to some embodiments of the present invention. -
FIG. 2 illustrates a block diagram of a transceiver according to some embodiments of the present invention. - The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the invention are shown. However, this invention should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.
- It also will be understood that, as used herein, the term “comprising” or “comprises” is open-ended, and includes one or more stated elements, steps and/or functions without precluding one or more unstated elements, steps and/or functions.
- The present invention is described below with reference to block diagrams and/or operational illustrations of methods and mobile terminals according to embodiments of the invention. It is understood that each block of the block diagrams and/or operational illustrations, and combinations of blocks in the block diagrams and/or operational illustrations, can be implemented by radio frequency, analog and/or digital hardware, and/or computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, and/or other programmable data processing apparatus in a mobile terminal, such that the instructions, which execute via the processor of the computer and/or other programmable data processing apparatus, create means for implementing the functions/acts specified in the block diagrams and/or operational block or blocks.
- These computer program instructions may also be stored in a computer-readable memory that can direct a mobile terminal to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instructions which implement the functions/acts specified in the block diagrams and/or operational block or blocks. It should also be noted that in some alternate implementations, the functions/acts noted in the blocks may occur out of the order noted in the operational illustrations. For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
- Various embodiments of the present invention will now be described with reference to the schematic block diagram of
FIG. 1 that illustrates an exemplary wireless communication system that includes amobile terminal 10 that communicates with awireless communications network 30 over a radiofrequency communication channel 28. For purposes of illustration only, the wireless communication system is assumed to be a WCDMA system that is compliant with the 3GPP specification. - The
mobile terminal 10 controls its transmission power over thecommunication channel 28 in response to a transmission power control (TPC) command from thenetwork 30. Themobile terminal 10 also controls its transmission power based on the quality of signals received from thenetwork 30. For example, themobile terminal 10 may stop transmitting when received signal quality falls below a threshold level, which may indicate that the mobile terminal is out-of-sync or that it otherwise may not be able to effectively communicate with thenetwork 30. Themobile terminal 10 may determine signal quality by estimating signal to interference ratios (SIRs) from pilot signals received from thenetwork 30. When the estimated SIRs fall below a threshold value, which may indicate an out-of-sync condition, themobile terminal 10 stops transmitting, and may thereby avoid interfering with communications between thenetwork 30 and other mobile terminals. Conversely when the estimated SIRs exceed the threshold value, themobile terminal 10 may begin and/or resume transmission. - The
mobile terminal 10 may remove bias from the SIR estimates according to the various embodiments of the present invention, which may allow more accurate detection of the out-of-sync and/or in-sync condition. Themobile terminal 10 may also restrict or prevent an increase and/or decrease of its transmission power based on the SIRs and when an out-of-sync condition has not been identified. For example, when the received signal quality (represented by the estimated SIRs) is below a threshold amount, but themobile terminal 10 determines that it is in-sync such that it can continue transmitting, themobile terminal 10 may ignore, or may modify its reaction to, a received TPC command that commands an increase or decrease in transmission output power. For example, restricting or preventing an increase in transmission output power may avoid or prevent themobile terminal 10 from unnecessarily interfering with communications between thenetwork 30 and other mobile terminals when themobile terminal 10 is uncertain about whether the channel conditions are sufficient to continue communication with thenetwork 30. Similarly, restricting decrease in the transmission output power may avoid unnecessarily dropping calls. - As illustrated in
FIG. 1 , themobile terminal 10 may include aportable housing 12, a keyboard/keypad 14, adisplay 16, aspeaker 18, amicrophone 20, aprocessor 22, amemory 24, and atransceiver 26. Thememory 24 may include one or more erasable programmable read-only memories (EPROM or Flash EPROM), battery backed random access memory (RAM), magnetic, optical, or other digital storage device, and may be separate from, or at least partially within, theprocessor 22. Themobile terminal 10 may, thereby, communicate with thenetwork 30 using radio frequency signals. The radio frequency signals may be communicated through anantenna 26 over thecommunication channel 28 with thenetwork 30. - As used herein, a “mobile terminal” includes, but is not limited to, a cellular mobile terminal; a personal communication terminal that may combine a cellular mobile terminal with data processing, facsimile and data communications capabilities; a personal data assistance (PDA) that can include a wireless transceiver, pager, Internet/intranet access, local area network interface, wide area network interface, Web browser, organizer, and/or calendar; and a computer or other device that includes a wireless transceiver. The
mobile terminal 10 may be configured to communicate according to one or more wireless communication protocols, including, but not limited to, ANSI-136, GSM, code division multiple access (CDMA), wideband-CDMA, CDMA2000, Enhanced Data Rates for GSM Evolution (EDGE), Universal Mobile Telecommunications System (UMTS), a wireless local area network (WLAN) protocol, including IEEE 802.11b-g, and Bluetooth, satellite protocols, private land mobile radio protocols, including PROJECT-25 and Tetra, and/or other communication protocols. Communication protocols as used herein may specify the information communicated, the timing, the frequency, the modulation, and/or the operations for setting-up and/or maintaining a communication connection. -
FIG. 2 illustrates atransceiver 200 that may, for example, be used in themobile terminal 10 shown inFIG. 1 according to various embodiments of the present invention. Information that is to be transmitted may be modulated by amodulator 202 and transmitted by atransmitter 204 through anantenna 206. Thetransmitter 204 controls its output transmission power based on a power level signal 208 from acombiner 221, and stops transmitting (reduces its transmission power to a very low value or substantially zero) based on a transmission enablesignal 210 from an out-of-sync detector 226. - Signals from the
antenna 206 are received by areceiver 212 where they are downconverted and sampled, and then coupled to a transmit power control (TPC)decoder 214, aSIR estimator 216, aRAKE receiver 218, and adelay estimator 220. TheRAKE receiver 218 has L delay taps or RAKE fingers. Thedelay estimator 220 estimates RAKE delays from the sampled received signal. TheSIR estimator 216 forms channels estimates (hi, where i=1 to L) for the L delay taps of theRAKE receiver 218 using, for example, a common pilot channel (CPICH) from thenetwork 30. The channel estimates are coupled to theRake receiver 218 for combining with the received sampled signal, and are coupled to theTPC decoder 214. The TPC decoder decodes the received sampled signal to identify a TPC command from thenetwork 30, and uses the TPC command to generate a control signal, which is coupled through thecombiner 221 to thetransmitter 204, to control the output transmission power of thetransmitter 204. Accordingly, thenetwork 30 may transmit a TPC command to thetransceiver 200 to control its output transmission power. - The
SIR estimator 216 also generates an estimate of interference in the received signal. The interference may be estimated using the CPICH, and may then be transformed to an estimate of the interference in the dedicated physical channel (DPCH) using a spreading factor difference between the CPICH and the DPCH. An estimate of the dedicated signal power may be made using, for example, dedicated pilot channel symbols. Signal to interference ratios (SIRs) may then be estimated using the estimated interference for the DPCH and the estimated dedicated signal power. The SIR estimates are coupled to aTX limit filter 222 and async filter 224. TheTX limit filter 222 and thesync filter 224 can remove at least a portion of bias in the SIR estimates based upon the number of dedicated pilot channel symbols (NDPCH) that are used for channel estimation and/or the number of RAKE fingers used to estimate the SIRs, as will be discussed later herein with regard to further embodiments of the filters. NDPCH may be known based on the slot format of thedata channel 28 which is provided by thenetwork 30 during the setup of the connection. - The
sync filter 224 generates a filtered SIR signal by, for example, averaging and/or integrating the SIR estimates over a predetermined time. The filtered SIR signal is compared by the out-of-sync detector 226 to an out-of-sync threshold. When the filtered SIR signal is below, or satisfies, the out-of-sync threshold, the out-of-sync detector 226 determines that an out-of-sync condition has occurred and substantially reduces the output transmission power of thetransmitter 204 to, for example, about zero. Accordingly, thetransmitter 204 may be substantially turned-off when an out-of-sync condition is detected. - The transmit (TX)
limit filter 222 may operate similar to thesync filter 224, except that it may have a faster response to rapid changes in the SIRs. Accordingly, an abrupt decrease in the received SIR may be indicated earlier by the filtered SIR signal from theTX limit filter 222 than by the filtered SIR signal from thesync filter 224. ATX limit detector 228 compares the filtered SIR signal from theTX limit filter 222 to a TX limit threshold. When the filtered SIR signal is below, or satisfies, the TX limit threshold, theTX limit detector 228 restricts or prevents changes in the transmission output power of thetransmitter 204. - In an example operation, when the SIR estimates abruptly decrease, but an out-of-sync condition has not yet been detected by the out-of-
sync detector 226, theTX limit detector 228 may restrict the transmission power of thetransmitter 204 to limited changes and/or may essentially latch (e.g., freeze) the transmission power to a power level, such as a current or previous power level. The transmission power level may be latched by, for example, using alimit signal 230 to latch the output power level signal 208 from thecombiner 221 to the power level associated with a current TPC command or an earlier TPC command, such as a TPC associated with an earlier slot. Consequently, when the channel signal quality has degraded to where a TPC from a network may be incorrectly interpreted or when thetransceiver 200 may otherwise be prone to incorrectly increasing and/or decreasing its transmission power, the transmission power may be restricted to limited changes and/or latched to a power level to preclude such incorrect increase or decrease. - The output transmission power level may continue to be restricted to limited changes and/or latched until the signal quality sufficiently improves as determined by the
TX limit detector 228, or until the signal quality sufficiently degrades so that the transmitter is essentially turned-off by the out-of-sync detector 226. - The threshold values used by the
TX limit detector 228 and/or the out-of-sync detector 226 may be based on a desired sensitivity of thetransceiver 200 to signal quality conditions where transmission power changes should be restricted or where transmission power should be reduced to about zero. - Bias or error between the estimated SIRs and the actual SIRs (for example between the mean of the estimated SIRs and the actual SIRs) may be at least partially removed by a bias removal module that may be part of the
TX limit filter 222 and/or thesync filter 224. Removing bias from the filtered SIR estimates may improve the ability of theTX limit detector 228 and/or the out-of-sync detector 226 to more accurately and/or quickly detect signal quality conditions in which the transmission power should be restricted or turned-off, which may be particularly advantageous for low SIR values. TheTX limit filter 222 and thesync filter 224 may remove at least a portion of bias in the SIR estimates based upon the number of dedicated pilot channel symbols (NDPCH) that are used for channel estimation and/or the number of RAKE fingers that are used to estimate the SIRs. - Bias may be estimated and at least partially removed from the estimated SIRs as described below. With reference to DPCH channel estimation, the de-spread, with respect to the DPCH channelization code, signal yt,f DPCH at time t, for Rake-finger f can be written as follows:
where hf is the channel for finger f, ut is the DPCH (pilot) symbol and et,f is the noise on finger f with variance σf 2. The channel estimate, averaged over NDPCH dedicated pilots may be determined as follows:
where p indicates that ut p is a pilot symbol. The SIR estimate for slot k can be determined as follows:
where nk is the number of fingers used for SIR computation in slot k and {circumflex over (σ)}f 2 is the estimate of the interference for finger f (obtained by scaling the CPICH interference estimate). The SIR estimate is filtered through an IIR filter (e.g., 222 or 224) in order to provide an averaged SIR estimate, as follows:
SIR k =λSIR k−1+(1−λ)SIR k′ (3)
Assuming that the SIR belongs to a stationary random process, the mean value, E(SIRk) may be as follows:
Assuming that the interference estimate for each finger is ideal, i.e. {circumflex over (σ)}f 2=σf 2, the mean value may be provided as follows:
Inserting equation (5) into equation (4) provides the following equation:
Equation (6) shows that the bias term in the SIR estimate depends on the number of fingers nk divided by the number of dedicated pilot symbols NDPCH in the transport format, which changes over time. - In some embodiments, bias may be compensated, assuming nk is constant for all slots, nk=n, by subtracting the bias term after IIR filtering, as follows:
- In some other embodiments, bias may be compensated, assuming nk is varying between slots, by subtracting the bias term before IIR filtering, as follows:
- The threshold values that should be used by the
TX limit detector 228 and the out-of-sync detector 226 may be determined as described below. In-sync and out-of-sync threshold values, Qin and Qout, respectively, and the TX limit threshold value (QTX— LIMIT) may be determined based on a relationship between SIR-symbol energy and combined TPC energy. This relationship may depend upon, for example, the number of TPC symbols NTPC, and/or the number of RAKE fingers used to estimate the SIRs. - For a reference channel of 12.2 kbps as defined by the 3GPP specification, UE Radio Transmission and Reception (FDD), Section A.3.1, 3GPP TS 25.101 (2002-06), 2002, the slot format is 11, and a NTPC=1 symbol (2 bits) may be used, where NDPCH=4 symbols (8 bits).
- For all other slot formats, the thresholds Qin, Qout, and QTX
— LIMIT may be compensated for the format of the channel by, for example, scaling by a factor 1/NTPC. Accordingly, the thresholds, Qin, Qout, and QTX— LIMIT may be described as follows:
The NDPCH value may only influence the bias compensation term and not the decision levels. Alternatively, these equations for thresholds, Qin, Qout, and QTX— LIMIT may be written to include the above-described bias compensation, and may be based on state information including, for example, whether a mobile terminal is in a soft handover mode or a compressed mode. - During a compressed mode, the spreading factor may be reduced by a factor of 2 and the DPCH Ec power (where Ec is the chip energy) may be doubled. Compressed mode may be handled by using slot formats ending with A and B. Compressed mode slots may use slot formats ending with a “B”, for which the number of DPCH pilot symbols and number of TPC symbols have been doubled to compensate for the spreading factor reduction. Accordingly, the pilot energy and TPC bit energy per time unit may be kept about constant. The value NDPCH entering into the filters, see Equation (8), may be changed based on the slot format, such as has been described for the non-compressed mode case. The thresholds Qin, Qout, and QTX
— LIMIT may be determined with NTPC set to NTPC for slot format A. - During soft-handover, the threshold values may be kept constant because of a potential loss of TPC detection performance. The in-sync threshold Qin may be determined from
where f (•) is a table giving the conversion gain loss of un-coherent combination of TPC symbols from NB different base stations, and may be further based on information available in the “TPC combination index”, which is information received from thenetwork 30, or based on f(NB)=1. - When
TX limit filter 222 responds faster to SIR changes than thesync filter 224, the filtered SIR values from theTX limit filter 222 may be noisier than those of thesync filter 224. The TX limit threshold value used by theTX limit detector 228 may be lower than the out-of-sync threshold value used by the out-of-sync detector 226 so as to reduce the occurrence of unwanted restriction of the output transmission power level due to noise fluctuations in the SIRs. For example, the TX limit threshold value may be −7 dB and the out-of-sync threshold value may be −5 dB. - When the filtered SIR values from the
TX limit filter 222 are less than a TX limit threshold value, the transmission power level may be restricted to an earlier output power level of an earlier slot. In contrast, when the filtered SIR value from thesync filter 224 is less than an out-of-sync threshold, thetransmitter 204 may be effectively turned-off by reducing the transmission power level to essentially zero. - In other embodiments of the present invention, a transceiver may be provided as shown in
FIG. 2 except that theTX limit filter 222 may be eliminated and the filtered SIR signal from thesync filter 224 may be coupled to both theTX limit detector 228 and the out-of-sync detector 226. The threshold value of theTX limit detector 228 may be based on the threshold value of the out-of-sync detector 226. For example, the threshold that may be used to cause restriction of transmission power changes may be set a predetermined amount above the threshold used to identify an out-of-sync condition. Accordingly, a degraded received signal may satisfy the threshold for restricting power changes before it satisfies the threshold for turning off thetransmitter 204. - Although embodiments of the invention have been described, for purposes of illustration only, in the context of a mobile terminal that restricts changes to its transmission power, according to various other embodiments of the present invention, a base station or another wireless device may restrict changes to its transmission power based on the operations and/or wireless transceiver described herein.
- In the drawings and specification, there have been disclosed embodiments of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being set forth in the following claims.
Claims (38)
Priority Applications (5)
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US10/612,373 US7149538B2 (en) | 2003-02-13 | 2003-07-02 | Wireless transceivers, methods, and computer program products for restricting transmission power based on signal-to-interference ratios |
DE602004006382T DE602004006382D1 (en) | 2003-02-13 | 2004-02-05 | WIRELESS TRANSMITTER RECEIVERS, METHOD AND COMPUTER PROGRAM PRODUCTS FOR LIMITING TRANSMISSION POWER ON THE BASIS OF SIGNAL INTERFERENCE RATIO |
AT04708351T ATE362236T1 (en) | 2003-02-13 | 2004-02-05 | WIRELESS TRANSMITTER-RECEIVER, METHOD AND COMPUTER PROGRAM PRODUCTS FOR LIMITING TRANSMIT POWER BASED ON SIGNAL-INTERFERENCE RATIOS |
PCT/EP2004/001041 WO2004073204A1 (en) | 2003-02-13 | 2004-02-05 | Wireless transceivers, methods, and computer program products for restricting transmission power based on signal- to-interference ratios |
EP04708351A EP1593209B1 (en) | 2003-02-13 | 2004-02-05 | Wireless transceivers, methods, and computer program products for restricting transmission power based on signal- to-interference ratios |
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US10/612,373 US7149538B2 (en) | 2003-02-13 | 2003-07-02 | Wireless transceivers, methods, and computer program products for restricting transmission power based on signal-to-interference ratios |
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Cited By (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050143117A1 (en) * | 2003-12-31 | 2005-06-30 | Infineon Technologies Morphics, Inc. | Signal-to-interference ratio estimation for CDMA |
US20050148357A1 (en) * | 2004-01-05 | 2005-07-07 | Nokia Corporation | Radio network relocation |
US20050250524A1 (en) * | 2004-05-06 | 2005-11-10 | Johan Nilsson | Methods and apparatus for fast downlink information of uplink out-of-synchronization |
US20060003786A1 (en) * | 2004-06-09 | 2006-01-05 | Nec Corporation | Mobile communication system, mobile terminal, transmit power control method in a mobile terminal, and program |
US20060223446A1 (en) * | 2005-03-29 | 2006-10-05 | Francis Dominique | Methods of detecting mobile stations not following power control commands |
US20060223447A1 (en) * | 2005-03-31 | 2006-10-05 | Ali Masoomzadeh-Fard | Adaptive down bias to power changes for controlling random walk |
WO2007129180A2 (en) | 2006-05-05 | 2007-11-15 | Nokia Corporation | Enhanced ue out-of-sync behavior with gated uplink dpcch or gated downlink f-dpch or dpcch transmission |
US20080043714A1 (en) * | 2006-08-16 | 2008-02-21 | Nokia Corporation | Multiradio scheduling including clock synchronization validity protection |
US20080090593A1 (en) * | 2006-10-12 | 2008-04-17 | Innovative Sonic Limited | Method and related apparatus for enhancing paging efficiency in a wireless communications system |
EP2009945A1 (en) * | 2006-03-31 | 2008-12-31 | NEC Corporation | Mobile communication terminal, synchronization judging circuit used in the mobile communication terminal, control method, and synchronization judging control program |
US20090086682A1 (en) * | 2007-10-01 | 2009-04-02 | Muhammad Ali Kazmi | Downlink Out of Sync Detection in Continuous Packet Connectivity |
US20100074119A1 (en) * | 2008-09-24 | 2010-03-25 | Qualcomm Incorporated | Opportunistic data forwarding and dynamic reconfiguration in wireless local area networks |
US20120008582A1 (en) * | 2006-01-13 | 2012-01-12 | Alcatel | Adaptive subcarrier allocation to a mobile terminal in a multi cell fdm or ofdm network |
US20120322495A1 (en) * | 2010-03-12 | 2012-12-20 | St-Ericsson Sa | Method of and Apparatus of Communication Between a Mobile Station and a Base Station |
US20130021992A1 (en) * | 2011-07-18 | 2013-01-24 | Motorola Mobility Llc | Method for facilitating synchronisation between a communications network and a wireless communications device operating in a cpc dtx mode and a wireless communications device |
US20130194938A1 (en) * | 2012-01-30 | 2013-08-01 | Renesas Mobile Corporation | Interference Control Mechanism in Multi-Band Communication |
RU2494546C2 (en) * | 2008-05-30 | 2013-09-27 | Телефонактиеболагет Лм Эрикссон (Пабл) | Synchronisation detection using bandwidth and antenna configuration |
US9055537B2 (en) | 2012-06-05 | 2015-06-09 | Qualcomm Incorporated | Methods and apparatus for sire-based DLTPC rejection |
US20150163686A1 (en) * | 2013-12-06 | 2015-06-11 | Qualcomm Incorporated | Apparatus and method for sire bias compensation |
Families Citing this family (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7522682B2 (en) * | 2004-12-29 | 2009-04-21 | Alcatel-Lucent Usa Inc. | Removing bias in a pilot symbol error rate for receivers |
ATE556560T1 (en) * | 2006-12-21 | 2012-05-15 | Sony Ericsson Mobile Comm Ab | POWER CONTROL FOR COMPRESSED MODE IN WCDMA SYSTEMS |
US7953140B2 (en) * | 2007-08-01 | 2011-05-31 | Broadcom Corporation | Method and apparatus to process dedicated pilot bits from multiple fingers |
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US8144712B2 (en) | 2008-08-07 | 2012-03-27 | Motorola Mobility, Inc. | Scheduling grant information signaling in wireless communication system |
US8428080B2 (en) * | 2010-09-16 | 2013-04-23 | Apple Inc. | Method to control reconfiguration of multiple radio access bearers in a wireless device |
GB2493394B (en) * | 2011-08-05 | 2014-01-22 | Renesas Mobile Corp | System and methods for detection of a synchronization condition |
EP2755428A1 (en) * | 2013-01-09 | 2014-07-16 | Sony Mobile Communications AB | Method for reducing power consumption of a mobile device and mobile device |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20010026544A1 (en) * | 2000-04-04 | 2001-10-04 | Tetsuya Miura | CDMA Transmitter/receiver |
US6456826B1 (en) * | 2000-02-25 | 2002-09-24 | Nokia Mobile Phones Ltd. | User equipment and procedure for handling possible out-of-synchronization condition in UMTS terrestrial radio access network for time division duplexing mode |
US20020136186A1 (en) * | 1999-12-24 | 2002-09-26 | Masatoshi Watanabe | Cdma terminal and cdma method |
US20020159514A1 (en) * | 2000-01-14 | 2002-10-31 | Kenichi Miyoshi | Sir measuring device and sir measuring method |
US20020196879A1 (en) * | 2000-11-09 | 2002-12-26 | Hitoshi Iochi | Desired wave/interference power ratio measuring circuit and desired wave/interference power ratio measuring method |
US20030022685A1 (en) * | 2001-01-05 | 2003-01-30 | Johan Nilsson | SIR estimation using delay time of power control commands |
US20030039217A1 (en) * | 2001-08-25 | 2003-02-27 | Samsung Electronics Co., Ltd. | Apparatus and method for transmitting/receiving uplink transmission power offset and HS-DSCH power level in a communication system employing HSDPA |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6185432B1 (en) | 1997-10-13 | 2001-02-06 | Qualcomm Incorporated | System and method for selecting power control modes |
JPH11145899A (en) | 1997-11-10 | 1999-05-28 | Matsushita Electric Ind Co Ltd | Transmission/reception equipment and radio transmission system |
JP3621310B2 (en) | 1999-10-07 | 2005-02-16 | 松下電器産業株式会社 | Wireless communication apparatus and transmission power control method |
CN1132357C (en) | 2000-08-21 | 2003-12-24 | 华为技术有限公司 | Method and device for measuring S/N ratio |
US6922389B1 (en) | 2000-11-15 | 2005-07-26 | Qualcomm, Incorporated | Method and apparatus for reducing transmission power in a high data rate system |
GB2401287B (en) * | 2001-02-28 | 2005-03-16 | Nec Corp | Receiver and method of operation thereof |
-
2003
- 2003-07-02 US US10/612,373 patent/US7149538B2/en not_active Expired - Fee Related
-
2004
- 2004-02-05 WO PCT/EP2004/001041 patent/WO2004073204A1/en active IP Right Grant
- 2004-02-05 EP EP04708351A patent/EP1593209B1/en not_active Expired - Lifetime
- 2004-02-05 AT AT04708351T patent/ATE362236T1/en not_active IP Right Cessation
- 2004-02-05 DE DE602004006382T patent/DE602004006382D1/en not_active Expired - Lifetime
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20020136186A1 (en) * | 1999-12-24 | 2002-09-26 | Masatoshi Watanabe | Cdma terminal and cdma method |
US20020159514A1 (en) * | 2000-01-14 | 2002-10-31 | Kenichi Miyoshi | Sir measuring device and sir measuring method |
US6456826B1 (en) * | 2000-02-25 | 2002-09-24 | Nokia Mobile Phones Ltd. | User equipment and procedure for handling possible out-of-synchronization condition in UMTS terrestrial radio access network for time division duplexing mode |
US20010026544A1 (en) * | 2000-04-04 | 2001-10-04 | Tetsuya Miura | CDMA Transmitter/receiver |
US20020196879A1 (en) * | 2000-11-09 | 2002-12-26 | Hitoshi Iochi | Desired wave/interference power ratio measuring circuit and desired wave/interference power ratio measuring method |
US20030022685A1 (en) * | 2001-01-05 | 2003-01-30 | Johan Nilsson | SIR estimation using delay time of power control commands |
US20030039217A1 (en) * | 2001-08-25 | 2003-02-27 | Samsung Electronics Co., Ltd. | Apparatus and method for transmitting/receiving uplink transmission power offset and HS-DSCH power level in a communication system employing HSDPA |
Cited By (39)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050143117A1 (en) * | 2003-12-31 | 2005-06-30 | Infineon Technologies Morphics, Inc. | Signal-to-interference ratio estimation for CDMA |
US7251497B2 (en) * | 2003-12-31 | 2007-07-31 | Infineon Technologies Ag | Signal-to-interference ratio estimation for CDMA |
US7389121B2 (en) * | 2004-01-05 | 2008-06-17 | Nokia Corporation | Radio network relocation |
US20050148357A1 (en) * | 2004-01-05 | 2005-07-07 | Nokia Corporation | Radio network relocation |
US8019374B2 (en) * | 2004-01-05 | 2011-09-13 | Nokia Corporation | Radio network relocation |
US20080214195A1 (en) * | 2004-01-05 | 2008-09-04 | Nokia Corporation | Radio network relocation |
US7551597B2 (en) * | 2004-05-06 | 2009-06-23 | Telefonaktiebolaget L M Ericsson (Publ) | Methods and apparatus for fast downlink information of uplink out-of-synchronization |
US20050250524A1 (en) * | 2004-05-06 | 2005-11-10 | Johan Nilsson | Methods and apparatus for fast downlink information of uplink out-of-synchronization |
US20060003786A1 (en) * | 2004-06-09 | 2006-01-05 | Nec Corporation | Mobile communication system, mobile terminal, transmit power control method in a mobile terminal, and program |
US7460879B2 (en) * | 2004-06-09 | 2008-12-02 | Nec Corporation | Mobile communication system, mobile terminal, transmit power control method in a mobile terminal, and program |
US20060223446A1 (en) * | 2005-03-29 | 2006-10-05 | Francis Dominique | Methods of detecting mobile stations not following power control commands |
US20060223447A1 (en) * | 2005-03-31 | 2006-10-05 | Ali Masoomzadeh-Fard | Adaptive down bias to power changes for controlling random walk |
US8831120B2 (en) * | 2006-01-13 | 2014-09-09 | Alcatel Lucent | Adaptive subcarrier allocation to a mobile terminal in a multi cell FDM or OFDM network |
US20120008582A1 (en) * | 2006-01-13 | 2012-01-12 | Alcatel | Adaptive subcarrier allocation to a mobile terminal in a multi cell fdm or ofdm network |
EP2009945A4 (en) * | 2006-03-31 | 2012-12-12 | Nec Corp | Mobile communication terminal, synchronization judging circuit used in the mobile communication terminal, control method, and synchronization judging control program |
US8311080B2 (en) * | 2006-03-31 | 2012-11-13 | Nec Corporation | Mobile communication terminal, synchronization judging circuit used in the mobile communication terminal, control method, synchronization judging control program |
EP2009945A1 (en) * | 2006-03-31 | 2008-12-31 | NEC Corporation | Mobile communication terminal, synchronization judging circuit used in the mobile communication terminal, control method, and synchronization judging control program |
US20090268785A1 (en) * | 2006-03-31 | 2009-10-29 | Kazunori Sato | Mobile Communication Terminal, Synchronization Judging Circuit Used in the Mobile Communication Terminal, Control Method, Synchronization Judging Control Program |
WO2007129180A2 (en) | 2006-05-05 | 2007-11-15 | Nokia Corporation | Enhanced ue out-of-sync behavior with gated uplink dpcch or gated downlink f-dpch or dpcch transmission |
EP2022181A4 (en) * | 2006-05-05 | 2013-08-21 | Nokia Corp | Enhanced ue out-of-sync behavior with gated uplink dpcch or gated downlink f-dpch or dpcch transmission |
EP2022181A2 (en) * | 2006-05-05 | 2009-02-11 | Nokia Corporation | Enhanced ue out-of-sync behavior with gated uplink dpcch or gated downlink f-dpch or dpcch transmission |
US8325703B2 (en) * | 2006-08-16 | 2012-12-04 | Nokia Corporation | Multiradio scheduling including clock synchronization validity protection |
US20080043714A1 (en) * | 2006-08-16 | 2008-02-21 | Nokia Corporation | Multiradio scheduling including clock synchronization validity protection |
US20080090593A1 (en) * | 2006-10-12 | 2008-04-17 | Innovative Sonic Limited | Method and related apparatus for enhancing paging efficiency in a wireless communications system |
US20090086682A1 (en) * | 2007-10-01 | 2009-04-02 | Muhammad Ali Kazmi | Downlink Out of Sync Detection in Continuous Packet Connectivity |
US8160075B2 (en) * | 2007-10-01 | 2012-04-17 | Telefonaktiebolaget Lm Ericsson (Publ) | Downlink out of sync detection in continuous packet connectivity |
RU2494546C2 (en) * | 2008-05-30 | 2013-09-27 | Телефонактиеболагет Лм Эрикссон (Пабл) | Synchronisation detection using bandwidth and antenna configuration |
US20100074119A1 (en) * | 2008-09-24 | 2010-03-25 | Qualcomm Incorporated | Opportunistic data forwarding and dynamic reconfiguration in wireless local area networks |
US8279794B2 (en) * | 2008-09-24 | 2012-10-02 | Qualcomm Incorporated | Opportunistic data forwarding and dynamic reconfiguration in wireless local area networks |
US20120322495A1 (en) * | 2010-03-12 | 2012-12-20 | St-Ericsson Sa | Method of and Apparatus of Communication Between a Mobile Station and a Base Station |
US9008715B2 (en) * | 2010-03-12 | 2015-04-14 | St-Ericsson Sa | Method of and apparatus of communication between a mobile station and a base station |
US20130021992A1 (en) * | 2011-07-18 | 2013-01-24 | Motorola Mobility Llc | Method for facilitating synchronisation between a communications network and a wireless communications device operating in a cpc dtx mode and a wireless communications device |
US9088940B2 (en) * | 2011-07-18 | 2015-07-21 | Intel Corporation | Method for facilitating synchronisation between a communications network and a wireless communications device operating in a CPC DTX mode and a wireless communications device |
US20130194938A1 (en) * | 2012-01-30 | 2013-08-01 | Renesas Mobile Corporation | Interference Control Mechanism in Multi-Band Communication |
US8837401B2 (en) * | 2012-01-30 | 2014-09-16 | Broadcom Corporation | Interference control mechanism in multi-band communication |
US9055537B2 (en) | 2012-06-05 | 2015-06-09 | Qualcomm Incorporated | Methods and apparatus for sire-based DLTPC rejection |
US20150163686A1 (en) * | 2013-12-06 | 2015-06-11 | Qualcomm Incorporated | Apparatus and method for sire bias compensation |
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US9706421B2 (en) * | 2013-12-06 | 2017-07-11 | Qualcomm Incorporated | Apparatus and method for sire bias compensation |
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WO2004073204A1 (en) | 2004-08-26 |
EP1593209B1 (en) | 2007-05-09 |
US7149538B2 (en) | 2006-12-12 |
EP1593209A1 (en) | 2005-11-09 |
ATE362236T1 (en) | 2007-06-15 |
DE602004006382D1 (en) | 2007-06-21 |
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